Junior Class 1 Answered
HOW CAN WE DETERMINE THE PROPERTIES OF AN ELEMENT WITH THE HELP OF MENDLEEV'S PERIODIC TABLE?
Asked by saiyamsikaria30 | 15 Jan, 2016, 06:15: PM
Expert Answer
- Mendeleev arranged elements in the increasing order of their atomic masses and observed that the elements showed repetition after certain intervals in their physical and chemical properties.
- He arranged the known elements in the increasing order of their atomic masses in horizontal rows, till he encountered an element which had properties similar to the first element.
- Mendeleev placed the element below the first element and started the second row of elements.
- Proceeding in this way, he created the first periodic table containing 63 elements, arranged according to their properties.
- There are seven horizontal rows in the periodic table, numbered from 1 to 7. These seven rows are called periods.
- There are eight vertical columns numbered from I to VIII. These eight columns are called groups. Groups I to VII are further divided into A and B sub-groups.
- The properties of elements in a particular period show regular gradation from the left to right.
Answered by | 15 Jan, 2016, 06:50: PM
